Patent Loophole

Ran into a story on Slashdot about a group of researchers that managed to find a loophole in a patent for a very expensive Hepatitis C drug. It is basically interferon (alpha 2b) stabilized with a sugar moiety. It looks as if all they did was find another site (other than the site that was included on the patent) on to which they could add the PEGylation (sugar) to stabilize the interferon and maintain it's biological function. The origonal paper about the alternative stabilization of interferon is in Nature Chemical Biology.
It's interesting to hear Professor Sunil Shaunak's take on the discovery. He definitely seems to be more interested in a cure as opposed to making money. The Slashdot comments of course praise him and his stance. I bet at least one lawyer's head rolls for leaving this gap in the original patent held by the pharma giant Roche.